The Social Brain

  title={The Social Brain},
  author={Robin I. M. Dunbar},
  journal={Current Directions in Psychological Science},
  pages={109 - 114}
  • Robin I. M. Dunbar
  • Published 1 April 2014
  • Psychology
  • Current Directions in Psychological Science
The social-brain hypothesis refers to a quantitative relationship between social-group size and neocortex volume in monkeys and apes. This relationship predicts a group size of approximately 150 for humans, which turns out to be the typical size of both social communities in small-scale societies and personal social networks in the modern world. This constraint on the size of social groups is partly cognitive and partly temporal. It gives rise to a layered structure in primate and human social… 

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